An issue with Time Warner Cable's Internet backbone disrupted the company's Internet and on demand services on Wednesday morning, the company said. The disruption started at 4.30 a.m. U.S. Eastern Time during routine network maintenance and affected all of the company's Internet service subscribers, said Time Warner Cable spokeswoman Bobby Amirshahi in an email. She couldn't say what exactly caused the disturbance. The company is still investigating the cause of the problem.